US 2011/0285301 A1 discloses a triac dimmer compatible switching mode power supply. Such a switching mode power supply is used for driving a lamp comprising one or more light emitting diodes. This switching mode power supply comprises a power factor correction controller and uses feedback for a primary side regulation and/or a secondary side regulation.
Arrangements having a relatively high power factor and a relatively low total harmonic distortion, while being based on a primary side regulation for saving components and reducing costs, are available on the market, but at least some of these arrangements are not dimmer compatible.